diff --git a/Dockerfile b/Dockerfile
index 035128a..0b29a95 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -18,6 +18,7 @@ RUN set -ex; \
         docker-cli \
     ;
 
-COPY kiwi-cron /usr/local/bin/
+COPY bin /usr/local/bin/
+COPY libexec /usr/local/libexec/
 
 CMD [ "kiwi-cron" ]
\ No newline at end of file
diff --git a/bin/kiwi-cron b/bin/kiwi-cron
new file mode 100755
index 0000000..ce925f9
--- /dev/null
+++ b/bin/kiwi-cron
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+# replace crontab, run crond
+/usr/local/libexec/kiwi-cron/schedule_dirs | crontab -
+exec crond -fd 8
\ No newline at end of file
diff --git a/kiwi-cron b/kiwi-cron
deleted file mode 100755
index 4660c02..0000000
--- a/kiwi-cron
+++ /dev/null
@@ -1,172 +0,0 @@
-#!/bin/sh
-
-crontab=''
-crontab_line () {
-  if [ -z "${crontab}" ]; then
-    crontab="${1}"
-  else
-    crontab="$( 
-      printf '%s\n%s' "${crontab}" "${1}"; 
-    )"
-  fi
-}
-
-print_cron_schedule() {
-  pcs_min="${1}"
-  pcs_hour="${2}"
-  pcs_day="${3}"
-  pcs_month="${4}"
-  pcs_weekday="${5}"
-  pcs_command="${6}"
-  
-  printf '%-8s%-8s%-8s%-8s%-8s%s\n' \
-    "${pcs_min}" "${pcs_hour}" "${pcs_day}" "${pcs_month}" "${pcs_weekday}" "${pcs_command}"
-}
-
-create_schedule() {
-  cs_every="${1:-1}"
-  cs_units="${2}"
-  cs_command="${3}"
-
-  if [ "${cs_every}" -eq 1 ]; then
-    cs_every=""
-  else
-    cs_every="/${cs_every}"
-  fi
-
-  # generate valid random schedule values
-  # generally, "nighttime" and "weekend" will be preferred.
-
-  # shellcheck disable=SC3028
-  rand_min=$(( RANDOM % 60 ))
-
-  # shellcheck disable=SC3028
-  # rand_hour=$(( RANDOM % 24 ))
-  rand_hour=$(( (21 + RANDOM % 7) % 24 ))
-
-  # shellcheck disable=SC3028
-  rand_day=$(( RANDOM % 31 + 1 ))
-
-  # shellcheck disable=SC3028
-  # rand_weekday=$(( RANDOM % 7 ))
-  rand_weekday=$(( (6 + RANDOM % 2) % 7 ))
-
-  # shellcheck disable=SC3028
-  # rand_month=$(( RANDOM % 12 + 1 ))
-  rand_month=$(( RANDOM % 2 + 1 ))
-
-  case "${cs_units}" in
-  minute)
-    print_cron_schedule \
-      "*${cs_every}" "*" "*" "*" "*" "${cs_command}" 
-    ;;
-  hour)
-    print_cron_schedule \
-      "${rand_min}" "*${cs_every}" "*" "*" "*" "${cs_command}" 
-    ;;
-  day)
-    print_cron_schedule \
-      "${rand_min}" "${rand_hour}" "*${cs_every}" "*" "*" "${cs_command}" 
-    ;;
-  week)
-    print_cron_schedule \
-      "${rand_min}" "${rand_hour}" "*" "*" "${rand_weekday}" "${cs_command}" 
-    ;;
-  month)
-    print_cron_schedule \
-      "${rand_min}" "${rand_hour}" "${rand_day}" "*${cs_every}" "*" "${cs_command}" 
-    ;;
-  year)
-    print_cron_schedule \
-      "${rand_min}" "${rand_hour}" "${rand_day}" "${rand_month}" "*" "${cs_command}" 
-    ;;
-  esac
-}
-
-dir_has_no_files () {
-  dhnf_directory="${1}"
-
-  # count files in directory
-  dhnf_filecount="$( 
-    find "${dhnf_directory}" -type f -mindepth 1 -maxdepth 1 \
-    | wc -l
-  )"
-
-  # true if empty
-  test "${dhnf_filecount}" -eq "0"
-}
-
-dir_to_unit () {
-  dtu_dirname="${1}"
-
-  case "${dtu_dirname}" in
-    minute|hour|day|week|month|year)
-      echo "${dtu_dirname}" 
-      ;;
-    
-    # truncated "daily"
-    dai) 
-      echo "day"
-      ;;
-    
-    # truncated "annually"
-    annual) 
-      echo "year"
-      ;;
-  esac
-}
-
-crontab_line '# crontab generated by kiwi-cron'
-crontab_line '# generation time: '"$(date)"
-crontab_line '#'
-crontab_line "$( 
-  print_cron_schedule \
-    "# min" "hour" "day" "month" "weekday" "command" 
-)"
-
-# check *ly dirs in "/kiwi-cron" directory
-schedule_dirs="$( 
-  find "/kiwi-cron" -type d -name "*ly" -mindepth 1 -maxdepth 1
-)"
-
-for schedule_dir in ${schedule_dirs}; do
-  # ignore if no files
-  if dir_has_no_files "${schedule_dir}"; then
-    continue
-  fi
-
-  # infer units by directory name
-  dir_name="${schedule_dir##*/}"
-  units="${dir_name%ly}"
-  units="$( dir_to_unit "${units}" )"
-
-  crontab_line "$( 
-    create_schedule "1" "${units}" "run-parts '${schedule_dir}'"
-  )"
-done
-
-# check dirs in "/kiwi-cron/every" directory
-every_schedule_dirs="$( 
-  find "/kiwi-cron/every" -type d -mindepth 1 -maxdepth 1
-)"
-
-for schedule_dir in ${every_schedule_dirs}; do
-  # ignore if no files
-  if dir_has_no_files "${schedule_dir}"; then
-    continue
-  fi
-
-  # infer schedule params by directory name
-  dir_name="${schedule_dir##*/}"
-  every="$( echo "${dir_name}" | awk -F_ '{print $1}' )"
-  units="$( echo "${dir_name}" | awk -F_ '{print $2}' )"
-  units="${units%s}"
-
-  crontab_line "$( 
-    create_schedule "${every}" "${units}" "run-parts '${schedule_dir}'"
-  )"
-done
-
-# replace crontab, run crond
-echo "${crontab}" | crontab -
-exec crond -fd 8
diff --git a/libexec/kiwi-cron/create_schedule b/libexec/kiwi-cron/create_schedule
new file mode 100755
index 0000000..792b346
--- /dev/null
+++ b/libexec/kiwi-cron/create_schedule
@@ -0,0 +1,62 @@
+#!/bin/sh
+
+this_script="$( readlink -f "${0}" )"
+this_dir="${this_script%/*}"
+
+cs_every="${1:-1}"
+cs_units="${2}"
+cs_command="${3}"
+
+if [ "${cs_every}" -eq 1 ]; then
+  cs_every=""
+else
+  cs_every="/${cs_every}"
+fi
+
+# generate valid random schedule values
+# generally, "nighttime" and "weekend" will be preferred.
+
+# shellcheck disable=SC3028 # RANDOM is defined in alpine's /bin/sh
+cs_rand_min=$(( RANDOM % 60 ))
+
+# shellcheck disable=SC3028
+# cs_rand_hour=$(( RANDOM % 24 ))
+cs_rand_hour=$(( (21 + RANDOM % 7) % 24 ))
+
+# shellcheck disable=SC3028
+cs_rand_day=$(( RANDOM % 31 + 1 ))
+
+# shellcheck disable=SC3028
+# cs_rand_weekday=$(( RANDOM % 7 ))
+cs_rand_weekday=$(( (6 + RANDOM % 2) % 7 ))
+
+# shellcheck disable=SC3028
+# cs_rand_month=$(( RANDOM % 12 + 1 ))
+cs_rand_month=$(( RANDOM % 2 + 1 ))
+
+case "${cs_units}" in
+minute)
+  "${this_dir}/print_cron_schedule" \
+    "*${cs_every}" "*" "*" "*" "*" "${cs_command}" 
+  ;;
+hour)
+  "${this_dir}/print_cron_schedule" \
+    "${cs_rand_min}" "*${cs_every}" "*" "*" "*" "${cs_command}" 
+  ;;
+day)
+  "${this_dir}/print_cron_schedule" \
+    "${cs_rand_min}" "${cs_rand_hour}" "*${cs_every}" "*" "*" "${cs_command}" 
+  ;;
+week)
+  "${this_dir}/print_cron_schedule" \
+    "${cs_rand_min}" "${cs_rand_hour}" "*" "*" "${cs_rand_weekday}" "${cs_command}" 
+  ;;
+month)
+  "${this_dir}/print_cron_schedule" \
+    "${cs_rand_min}" "${cs_rand_hour}" "${cs_rand_day}" "*${cs_every}" "*" "${cs_command}" 
+  ;;
+year)
+  "${this_dir}/print_cron_schedule" \
+    "${cs_rand_min}" "${cs_rand_hour}" "${cs_rand_day}" "${cs_rand_month}" "*" "${cs_command}" 
+  ;;
+esac
diff --git a/libexec/kiwi-cron/print_cron_schedule b/libexec/kiwi-cron/print_cron_schedule
new file mode 100755
index 0000000..10067c9
--- /dev/null
+++ b/libexec/kiwi-cron/print_cron_schedule
@@ -0,0 +1,11 @@
+#!/bin/sh
+
+pcs_minute="${1}"
+pcs_hour="${2}"
+pcs_day="${3}"
+pcs_month="${4}"
+pcs_weekday="${5}"
+pcs_command="${6}"
+
+printf '%-8s%-8s%-8s%-8s%-8s%s\n' \
+  "${pcs_minute}" "${pcs_hour}" "${pcs_day}" "${pcs_month}" "${pcs_weekday}" "${pcs_command}"
diff --git a/libexec/kiwi-cron/print_crontab b/libexec/kiwi-cron/print_crontab
new file mode 100755
index 0000000..13f4793
--- /dev/null
+++ b/libexec/kiwi-cron/print_crontab
@@ -0,0 +1,2 @@
+#!/bin/sh
+
diff --git a/libexec/kiwi-cron/schedule_dirs b/libexec/kiwi-cron/schedule_dirs
new file mode 100755
index 0000000..8214536
--- /dev/null
+++ b/libexec/kiwi-cron/schedule_dirs
@@ -0,0 +1,101 @@
+#!/bin/sh
+
+this_script="$( readlink -f "${0}" )"
+this_dir="${this_script%/*}"
+
+crontab=''
+crontab_line () {
+  if [ -z "${crontab}" ]; then
+    crontab="${1}"
+  else
+    crontab="$( 
+      printf '%s\n%s' "${crontab}" "${1}"; 
+    )"
+  fi
+}
+
+dir_has_no_files () {
+  dhnf_directory="${1}"
+
+  # count files in directory
+  dhnf_filecount="$( 
+    find "${dhnf_directory}" -type f -mindepth 1 -maxdepth 1 \
+    | wc -l
+  )"
+
+  # true if empty
+  test "${dhnf_filecount}" -eq "0"
+}
+
+dir_to_unit () {
+  dtu_dirname="${1}"
+
+  case "${dtu_dirname}" in
+    # truncated "daily"
+    dai) 
+      echo "day"
+      ;;
+    
+    # truncated "annually"
+    annual) 
+      echo "year"
+      ;;
+
+    *)
+      echo "${dtu_dirname}" 
+      ;;
+  esac
+}
+
+crontab_line '# crontab generated by kiwi-cron'
+crontab_line '# generation time: '"$(date)"
+crontab_line '#'
+crontab_line "$( 
+  "${this_dir}/print_cron_schedule" \
+    "# min" "hour" "day" "month" "weekday" "command" 
+)"
+
+# check *ly dirs in "/kiwi-cron" directory
+schedule_dirs="$( 
+  find "/kiwi-cron" -type d -name "*ly" -mindepth 1 -maxdepth 1
+)"
+
+for schedule_dir in ${schedule_dirs}; do
+  # ignore if no files
+  if dir_has_no_files "${schedule_dir}"; then
+    continue
+  fi
+
+  # infer units by directory name
+  dir_name="${schedule_dir##*/}"
+  units="${dir_name%ly}"
+  units="$( dir_to_unit "${units}" )"
+
+  crontab_line "$( 
+    "${this_dir}/create_schedule" "1" "${units}" "run-parts '${schedule_dir}'"
+  )"
+done
+
+# check dirs in "/kiwi-cron/every" directory
+every_schedule_dirs="$( 
+  find "/kiwi-cron/every" -type d -mindepth 1 -maxdepth 1
+)"
+
+for schedule_dir in ${every_schedule_dirs}; do
+  # ignore if no files
+  if dir_has_no_files "${schedule_dir}"; then
+    continue
+  fi
+
+  # infer schedule params by directory name
+  dir_name="${schedule_dir##*/}"
+  every="$( echo "${dir_name}" | awk -F_ '{print $1}' )"
+  units="$( echo "${dir_name}" | awk -F_ '{print $2}' )"
+  units="${units%s}"
+
+  crontab_line "$( 
+    "${this_dir}/create_schedule" "${every}" "${units}" "run-parts '${schedule_dir}'"
+  )"
+done
+
+echo "${crontab}"